transcranial ultrasound

PURPOSE: In patients undergoing endovascular thrombectomy (EVT) with acute ischemic stroke (AIS), dynamic cerebral autoregulation (dCA) may minimize neurological injury from blood pressure fluctuations. This study set out to investigate the function of dCA in predicting clinical outcomes following EVT. METHODS: 43 AIS of the middle cerebral or internal carotid artery patients underwent with EVT, and 43 healthy individuals (controls) were enrolled in this case control research...

Acute stroke is one of the most common neurologic emergencies encountered by emergency clinicians. While point of care ultrasound has been a core part of emergency clinicians' training and practice for many years, the use of specialized ultrasound modalities in the care of acute ischemic stroke has not been as widely adopted. This review discusses the use of ultrasound in acute stroke, with a focus on applications of interest to emergency clinicians. Transcranial Doppler, carotid Doppler, microembolic signal detection, transthoracic echocardiography, evaluation for collateral circulation and optic nerve sheath diameter measurement are discussed in a case-based format, with a focus on practical applications for emergency clinicians...

BACKGROUND: Carotid atherosclerosis is often mentioned as one of the main causes of stroke. Currently, embolization is considered the most common mechanism that causes ischemic strokes due to atherosclerotic lesions in the carotid artery. Transcranial Doppler (TCD) ultrasound provides relatively inexpensive, noninvasive, real-time measurement of blood flow characteristics and cerebrovascular hemodynamics within brain arteries. The pulsatile index measured by transcranial Doppler is a parameter that indicates the degree of elasticity of the blood vessels of the brain...

Transcranial ultrasonic neuromodulation is a rapidly burgeoning field where low-intensity transcranial focused ultrasound (tFUS), with exquisite spatial resolution and deep tissue penetration, is used to non-invasively activate or suppress neural activity in specific brain regions. Over the past decade, there has been a rapid increase of tFUS neuromodulation studies in healthy humans and subjects with central nervous system (CNS) disease conditions, including a recent surge of clinical investigations in patients...

INTRODUCTION: Prehospital identification of intracerebral haemorrhage (ICH) in suspected stroke cases may enable the initiation of appropriate treatments and facilitate better-informed transport decisions. This scoping review aims to examine the literature to identify early clinical features and portable devices for the detection of ICH in the prehospital setting. METHODS: Three databases were searched via Ovid (MEDLINE, EMBASE and CENTRAL) from inception to August 2022 using prespecified search strategies...

BACKGROUND: Invasive treatments like radiofrequency stereotactic lesioning or deep brain stimulation of the globus pallidus internus can resolve drug-resistant status dystonicus (SD). However, these open procedures are not always feasible in patients with SD. OBJECTIVE: The aim was to report the safety and efficacy of simultaneous asleep bilateral transcranial magnetic resonance-guided focused ultrasound (MRgFUS) pallidotomy for life-threatening SD. METHODS: We performed bilateral simultaneous MRgFUS pallidotomy under general anesthesia in 2 young patients with pantothenate kinase-associated neurodegeneration and GNAO1 encephalopathy...

BACKGROUND: Post-stroke cognitive impairment (PSCI) is the focus and difficulty of poststroke rehabilitation intervention with an incidence of up to 61%, which may be related to the deterioration of cerebrovascular function. Computer-aided cognitive training (CACT) can improve cognitive function through scientific training targeting activated brain regions, becoming a popular training method in recent years. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, can regulate the cerebral vascular nerve function, and has an effect on the rehabilitation of cognitive dysfunction after stroke...

OBJECTIVE: Transcranial focused ultrasound (tFUS) is being explored for neuroscience research and clinical applications due to its ability to affect precise brain regions noninvasively. The ability to target specific brain regions and localize the beam during these procedures is important for these applications to avoid damage and minimize off-target effects. Here, we present a method to combine optical tracking with magnetic resonance (MR) acoustic radiation force imaging to achieve targeting and localizing of the tFUS beam...

Numerous driven techniques have been utilized to assess dynamic cerebral autoregulation (dCA) in healthy and clinical populations. The current review aimed to amalgamate this literature and provide recommendations to create greater standardization for future research. The PubMed database was searched with inclusion criteria consisting of original research articles using driven dCA assessments in humans. Risk of bias were completed using Scottish Intercollegiate Guidelines Network and Methodological Index for Non-Randomized Studies...

INTRODUCTION: Cerebral blood flow (CBF) declines with age and abnormalities in CBF are associated with age-related cerebrovascular disease and neurodegeneration. Women have higher CBF than men, although this sex-difference diminishes to some extent with age in healthy subjects. The physiological drivers of these age/sex differences are uncertain, but might be secondary to age and sex-differences in haemoglobin (Hb) level. Hb levels are inversely correlated with CBF, are lower in women, and decline with age in men, but the interrelations between these factors have not been explored systematically either in healthy subjects or across the full age-range in patients with vascular risk factors...

Background  Continuous monitoring using implantable cardiac monitors (ICMs) results in atrial fibrillation (AF) detection rates of up to 30% in patients with cryptogenic stroke (CS). Although higher age is an independent risk factor for AF, there are no age-specific recommendations for the implantation of ICM. Objective  The aim of this study was to analyze age-related AF rates in patients with CS and continuous rhythm monitoring, to determine the rates of oral anticoagulation (OAC) and recurrent cerebrovascular events (stroke or transient ischemic attack) in patients with ICM-detected AF, and to describe the temporal relationship of AF detection and recurrent cerebrovascular events...

BACKGROUND: The nucleus accumbens (NAc) is a key node of the brain reward circuit driving reward-related behavior. Dysregulation of NAc has been demonstrated to contribute to pathological markers of addiction in substance use disorder (SUD) making it a potential therapeutic target for brain stimulation. Transcranial focused ultrasound (tFUS) is an emerging non-invasive brain stimulation approach that can modulate deep brain regions with a high spatial resolution. However, there is currently no evidence showing how the brain activity of NAc and brain functional connectivity within the reward network neuromodulated by tFUS on the NAc...

Transcranial focused ultrasound (tFUS) has emerged as a new mode of non-invasive brain stimulation (NIBS), with its exquisite spatial precision and capacity to reach the deep regions of the brain. The placement of the acoustic focus onto the desired part of the brain is critical for successful tFUS procedures; however, acoustic wave propagation is severely affected by the skull, distorting the focal location/shape and the pressure level. High-resolution (HR) numerical simulation allows for monitoring of acoustic pressure within the skull but with a considerable computational burden...

BACKGROUND: Non-invasive brain stimulation techniques such as transcranial magnetic stimulation and transcranial direct current stimulation hold promise for inducing brain plasticity. However, their limited precision may hamper certain applications. In contrast, Transcranial Ultrasound Stimulation (TUS), known for its precision and deep brain targeting capabilities, requires further investigation to establish its efficacy in producing enduring effects for treating neurological and psychiatric disorders...

BACKGROUND: Subarachnoid hemorrhage (SAH) patients with cerebral autoregulation (CA) impairment at an early post-SAH period are at high risk of unfavorable outcomes due to delayed cerebral ischemia (DCI) or other complications. Limited evidence exists for an association between early-stage CA impairments and SAH patient outcomes. The objective of this prospective study was to explore associations between CA impairments detected in early post-SAH snapshot examinations and patient outcomes...

The efficacy of extracranial-intracranial (EC-IC) bypass in preventing ischemic stroke progression and recurrence is controversial. As per the current hypothesis, EC-IC bypass is most beneficial for patients with persistent hemodynamic insufficiency. Hence, various approaches have been used to evaluate hemodynamic insufficiency, including repeated single photon emission CT (SPECT) imaging or continuous monitoring of cerebral flow with transcranial Doppler ultrasound (TCD). However, both modalities are time- and resource-intensive...

Wearable technology and neuroimaging equipment using photoplethysmography (PPG) have become increasingly popularized in recent years. Several investigations deriving pulse rate variability (PRV) from PPG have demonstrated that a slight bias exists compared to concurrent heart rate variability (HRV) estimates. PPG devices commonly sample at ~20-100 Hz, where the minimum sampling frequency to derive valid PRV metrics is unknown. Further, due to different autonomic innervation, it is unknown if PRV metrics are harmonious between the cerebral and peripheral vasculature...

BACKGROUND Bow hunter syndrome is a rare disease that is often overlooked. It presents with complex and variable clinical symptoms and causes, making diagnosis and treatment challenging. This case report focuses on a young patient with bilateral bow hunter syndrome, possibly caused by the loss of cervical physiological curvature. The aim is to enhance understanding and awareness of the disease. It is important to consider the possibility of bow hunter syndrome in young patients with long-term poor neck posture and symptoms such as dizziness, nausea, vomiting, and neck rotation-related symptoms...

Ultrasound evaluation of the brain is performed through acoustic windows. Transcranial Doppler has long been used to monitor patients with subarachnoid hemorrhage for cerebral vasospasm. Transcranial color-coded sonography permits parenchymal B-mode imaging and duplex evaluation. Transcranial ultrasound may also be used to assess the risk of delayed cerebral ischemia, screen patients for the presence of elevated intracranial pressure, confirm the diagnosis of brain death, measure midline shift, and detect ventriculomegaly...

OBJECTIVE: To investigate the early prediction value of transcranial Doppler ultrasound (TCD) combined with serum melatonin level for delayed cerebral ischemia (DCI) caused by subarachnoid hemorrhage (SAH). METHODS: This paper is a prospective study. A total of 120 patients with SAH treated were included. The patients were divided into the DCI group (40 cases) and non-DCI group (80 cases) according to whether DCI occurred 14 days after SAH (DCI usually occurs 4 to 14 d after bleeding)...